I really don't know what I'm doing wrong but Melodyne quantize seems to suck pretty badly to the point where I just don't use it any more. 
 
For instance, I did a test on a 12 bar guitar solo consisting of nothing but 16th notes. The timing wasn't too bad (I played it with a lazy feel) but I wanted to see how tight I could make it with Melodyne, just out of curiosity. So I just went ahead and applied a 16th-note quantize to the whole part using the Quantize Time macro. The results were atrocious - it's blatantly quantizing some notes to the 32nd note grid, effectively giving it a dotted 16th feel. Why would it even do that? If I took an equivalent MIDI track with the same timing and quantized it to 16th notes, you can bet your ass all the notes would fall squarely on the 16th note grid. 
 
Is there something I'm doing wrong here? I have the grid set to 16th notes and I'm quantizing to 16th notes with the macro. To my mind, that should guarantee that none of the notes would land anywhere but right on the 16th note divisions, and certainly note halfway between 2 16th notes. 
 
Here's an example of what I mean, using 3 notes of the solo. First, the pre-quantized notes. The grid is set to 16ths. As you can see, the 3 notes are ahead of the grid lines. The quantize is set to 16ths but I haven't yet applied it with the slider. 
 

 
Now here's what it looks like after the quantize. The middle note, instead of being moved back to the line like the other two, has planted itself midway between two lines. 
 

 
Now, just to prove that it's quantized the middle note to a 32nd note grid, here's what it looks like with the 32nd grid enabled: 
 

 
It's bang on a 32nd note division, even though the quantize value is set to 1/16. I'd really like to know why Melodyne sometimes does this...I get the feeling there's something I'm not understanding here, but even so it kind of sucks that it doesn't just work consistently and easily. I've quantized other guitar parts where it's done every note perfectly, but all too often I get this suckiness. 

I have seen this as well with other options available, and have had to take a step back to recognize my methodology (i.e. foolishness)... A co-worker once threw out a comment that gave me a chuckle, but has been echoed here many times... "Typical engineer for you... apply an $80,000 fix to a $5 part!"
 
If something requires "intense surgery" to fix with a "tool set," I have forced myself to step back and record another take. 3 hours of surgery is a waste compared to 5 minutes of playing it again, and I have found the new comping to fill this gap nicely... I will play till I mess up, stop, backtrack 2 bars and record again, then comp when done.
 
For me, if I am using tools to modifying a few notes, that is fine and a good use... but if I am trying to "warp" a passage that *I* created... the simplest fix it to do it again.

mettelus
I have seen this as well with other options available, and have had to take a step back to recognize my methodology (i.e. foolishness)... A co-worker once threw out a comment that gave me a chuckle, but has been echoed here many times... "Typical engineer for you... apply an $80,000 fix to a $5 part!"
 
If something requires "intense surgery" to fix with a "tool set," I have forced myself to step back and record another take. 3 hours of surgery is a waste compared to 5 minutes of playing it again, and I have found the new comping to fill this gap nicely... I will play till I mess up, stop, backtrack 2 bars and record again, then comp when done.
 
For me, if I am using tools to modifying a few notes, that is fine and a good use... but if I am trying to "warp" a passage that *I* created... the simplest fix it to do it again.

Yeah I'm well aware that it's a tool which shouldn't be overdone in every situation, and to be honest I had no intention of rigidly quantizing this part...I was just putting Melodyne through it's paces (given the reputation it has). However, there ARE some situations in which I'd like to quantize rigidly. It depends on the style of the music. If I was, for example, laying down a guitar part in some tight electro-funk, that rigid quantize sounds appropriate. 

I am with you, trust me. I have moments where I will simply "stress test" things and often come up with "epic fails." After I see glitches in things like your OP, I will often look for other options.
 
I am admittedly not a guru on audio snap (and honestly wish I had begun to learn it 8 years ago instead of 2 months ago!!), but I will say that the more I have learned, the more I am impressed with it. One of these days, I may become savvy enough with it to use it for "intense surgery"... but so far it appears to have the capability.

mettelus
I am with you, trust me. I have moments where I will simply "stress test" things and often come up with "epic fails." After I see glitches in things like your OP, I will often look for other options.
 
I am admittedly not a guru on audio snap (and honestly wish I had begun to learn it 8 years ago instead of 2 months ago!!), but I will say that the more I have learned, the more I am impressed with it. One of these days, I may become savvy enough with it to use it for "intense surgery"... but so far it appears to have the capability.

I too have been negligent in not learning Audiosnap, and I've heard a couple of people here say that they've found it better than Melodyne for quantizing. Maybe I'll get up to speed on it tomorrow. It's kind of disappointing though, because I'd much rather do all of my pitch and time jiggery pokery with the one tool, and admittedly Melodyne integration is pretty damn cool.